MCT8316Z: DIR pin has no effect

Hi,

We are using an MCT8316ZTEVM with an external cpu to evaluate the driver (MCT8316 - HW variant).

When the PWM frequency is low - 20 kHz, the driver works as expected. However, when we change the PWM frequency to 120khz, we can't change the rotation direction by toggling DIR pin.

Even if the driver enters brake mode (by toggling the BRAKE pin), the direction doesn't change. The same happens when the duty cycle is lowered to zero, (i.e. no direction changing). Only if the driver enters sleep mode, the direction can be changed.

What's the reason for this behavior and why is it dependent on the PWM frequency?

The datasheet mentions this driver supports up to 200khz.

Kind regards